The present invention relates, generally, to oral osmotic drug delivery
systems, methods of preparing same, and methods of using oral osmotic
drug delivery systems to provide controlled delivery of a drug that is
provided in an amount of from about 8 mg to about 20 mg. The oral osmotic
drug delivery systems include a drug layer, an osmotic layer, and an
outer coating surrounding the drug layer and osmotic layer, where the
outer coating includes at least one opening therein that is provided
adjacent the drug layer. The composition (% fines), shape, and weight
gain of the oral osmotic delivery systems may be modified in order to
provide for optimized release of the drug contained therein.